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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Determination of trace metals in lubricating oils by ICP-OES. / Determination of trace metals in lubricating oils by inductively coupled plasma-optical emission spectrometry.

Tekie, Haile Araya January 2013 (has links)
M. Tech. Chemistry. / Methods developed for the analysis of used oil can play a vital role in monitoring the condition of engines and may help to improve overall equipment effectiveness. Quantification of trace elements in used lubricating oil forms a vital part in monitoring engine conditions and impact on the environment. The main objective of this work is to investigate methods used for the accurate determination of trace elements in lubricating oils. In this study, inductively coupled plasma-optical emission spectrometry (ICP-OES) was used for the determination of trace elements (Ag, Ba, Cu, Mn and Ni) in lubricating oils.
42

Graphite furnace capacitively coupled plasma atomic emission spectrometry in the determination of trace metals in biological andenvironmental samples

曾令建, Tsang, Ling-kin, Simon. January 1998 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
43

Ion-exchange sample probe for laser ablation-ICP-AES

葉鴻釗, Yip, Hung-chiu. January 1998 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
44

Interfaces for capillary electrophoresis-inductively coupled plasma-atomic emission spectroscopy

Chan, Yan-ying., 陳恩影. January 1999 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
45

Investigation of graphite furnace capacitively coupled plasma atomic spectrometry for the determination of metals and silica in water andair particulate matter

張兆發, Cheung, Siu-fat, Eric. January 1999 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
46

Inductively Coupled Corrosion Potential Sensor for Remote Passive Monitoring of New and Existing Civil Structures

PERVEEN, KHALADA 06 May 2013 (has links)
The thesis describes development and optimization process of an inductively coupled coil corrosion potential sensor for long-term civil structure health monitoring remotely. This is of growing interest for decreasing the maintenance cost, reducing the deterioration significantly and increasing the safety. The thesis is organized accordingly introduction, circuit modeling of the sensor, optimization and fabrication of the sensors and the simulated and experimental results from new and existing civil structure. The two geometrical design, cylindrical shape and Printed Circuit Board (PCB) based sensor parts of this research and their encapsulation technique for long-term enduring in harsh and corrosive environment of the civil infrastructure is described in the thesis. Results of an accelerated corrosion test on an embedded cylindrical shaped sensor indicates that the corrosion potential can be monitored with less than 10 mV resolution with a sensor sensitivity of ~0.73 kHz/mV. The last part describes a novel technique for a PCB sensor to simulate the existing structure already contaminated with corrosive substances such as chlorides. Two encapsulation techniques, non-conductive epoxy sealed and PLEXIGLAS with air gap sealed embedded PCB sensors response are compared from the accelerated corrosion test on new and built-in civil structure. Finally, results from the accelerated corrosion tests using the two encapsulation techniques mentioned above demonstrate that the embedded sensor in an existing structure may take up to 60 days to see the significant corrosion with a sensor sensitivity of ~ 1.53 kHz/mV or ~ 1.63 kHz/mV respectively. Since chlorides take many years to diffuse into concrete used for civil structures these sensors will respond fast enough to be used in existing structures as well as in new structures.
47

Characterization of Pb and selected trace elements in amazonitic K-feldspar

Sokolov, Maria, 1969- January 2006 (has links)
Amazonitic K-feldspar is characteristic of evolved granitic pegmatites of NYF (niobium-yttrium-fluorine) type, associated with A-type granite emplacement. In this work, I focus on four notable examples of such an association: (1) West Keivy, Kola Peninsula, Russia, (2) Saint-Ludger-de-Milot, Quebec, (3) Lac Sairs, Quebec, and (4) Morefield, Virginia. A fifth locality, the Broken Hill metamorphosed exhalative-type volcanogenic deposits in Australia, is an unusual type of amazonitic K-feldspar formed in an ore environment. A total of nineteen samples of amazonitic K-feldspar were characterized geochemically and mineralogically on the basis of X-ray diffraction, electron-microprobe and laser-ablation ICP-MS analyses. Lead, as an essential requirement for formation of the blue-green amazonitic color, has received particular attention. In every case, the analytical data show elevated amounts of Pb and rare alkalis, which strongly partition into the K-rich phase of the perthite intergrowth. Unusual micrometric grains, highly enriched in Pb, are found in cracks in the material from West Keivy. Some of the grains represent a new mineral species, a Pb-dominant feldspar. The presence of amazonitic K-feldspar in a granitic pegmatite is more than a curiosity. It can shed light on important petrogenetic issues such as metasomatic rejuvenation of crustal rocks prior to regional melting in a period of extension.
48

Development of inductively coupled plasma spectroscopic methods for the determination of metals in beluga (delphinapterus leucas) and pygmy sperm (kogia breviceps) whale liver samples/

Parlayan, Filiz. Eanes, Ritchie January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005 / Keywords: ICP-OES, Chemometrics methods, internal standardization, matrix effects. Includes bibliographical references (leaves. 111-120).
49

Investigation of graphite furnace capacitively coupled plasma atomic spectrometry for the determination of metals and silica in water and air particulate matter /

Cheung, Siu-fat, Eric. January 1999 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2000. / Includes bibliographical references (leaf 153).
50

Ion-exchange sample probe for laser ablation-ICP-AES /

Yip, Hung-chiu. January 1998 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 154).

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